package com.TT.ticket.unsafe;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * 同理可证 java.util.ConcurrentModificationException
 * 1.Collections.synchronizedSet(new HashSet<>());
 * 2.new CopyOnWriteArraySet<>();
 */
public class SetTest {

    public static void main(String[] args) {
        //Set<String> set = new HashSet<>();
        //Set<String> set = Collections.synchronizedSet(new HashSet<>());
        Set<Object> set = new CopyOnWriteArraySet<>();

        for(int i=1;i<=10;i++){
            new Thread(()->{
                set.add(UUID.randomUUID().toString().substring(0,5));
                System.out.println(set);
            },String.valueOf(i)).start();
        }
    }


}
